<template>

  <div class="app-container">

    <!--查询表单-->
    <el-form :inline="true" class="demo-form-inline">

      <!-- 所属分类：级联下拉列表 -->
      <!-- 一级分类 -->
      <el-form-item label="课程类别">
        <el-select
          v-model="searchObj.subjectParentId"
          placeholder="请选择"
          @change="subjectLevelOneChanged">
          <el-option
            v-for="subject in oneSubjectList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"/>
        </el-select>

        <!-- 二级分类 -->
        <el-select v-model="searchObj.subjectId" placeholder="请选择">
          <el-option
            v-for="subject in twoSubjectList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"/>
        </el-select>
      </el-form-item>

      <!-- 标题 -->
      <el-form-item>
        <el-input v-model="searchObj.title" placeholder="课程标题"/>
      </el-form-item>
      <!-- 讲师 -->
      <el-form-item>
        <el-select
          v-model="searchObj.teacherId"
          placeholder="请选择讲师">
          <el-option
            v-for="teacher in teacherList"
            :key="teacher.id"
            :label="teacher.name"
            :value="teacher.id"/>
        </el-select>
      </el-form-item>

      <el-button type="primary" icon="el-icon-search" @click="getCourseList()">查询</el-button>
      <el-button type="default" @click="resetData()">清空</el-button>
    </el-form>
    <!-- 表格 -->
    <el-table
      v-loading="listLoading"
      :data="courseList"
      element-loading-text="数据加载中"
      border
      fit
      highlight-current-row
      row-class-name="myClassList">

      <el-table-column
        label="序号"
        width="70"
        align="center">
        <template slot-scope="scope">
          {{ (current - 1) * limit + scope.$index + 1 }}
        </template>
      </el-table-column>

      <el-table-column label="课程信息" width="470" align="center">
        <template slot-scope="scope">
          <div class="info">
            <div class="pic">
              <img :src="scope.row.cover" alt="scope.row.title" width="150px">
            </div>
            <div class="title">
              <a href="">{{ scope.row.title }}</a>
              <p>{{ scope.row.lessonNum }}课时</p>
            </div>
          </div>

        </template>
      </el-table-column>

      <el-table-column label="创建时间" align="center">
        <template slot-scope="scope">
          {{ scope.row.createTime.substr(0, 10) }}
        </template>
      </el-table-column>
      <el-table-column label="发布时间" align="center">
        <template slot-scope="scope">
          {{ scope.row.updateTime.substr(0, 10) }}
        </template>
      </el-table-column>
      <el-table-column label="价格" width="100" align="center">
        <template slot-scope="scope">
          {{ Number(scope.row.price) === 0 ? '免费' :
          '¥' + scope.row.price.toFixed(2) }}
        </template>
      </el-table-column>
      <el-table-column prop="buyCount" label="付费学员" width="100" align="center">
        <template slot-scope="scope">
          {{ scope.row.buyCount }}人
        </template>
      </el-table-column>

      <el-table-column label="操作" width="150" align="center">
        <template slot-scope="scope">
          <router-link :to="'/teach/course/info/'+scope.row.id">
            <el-button type="text" size="mini" icon="el-icon-edit">编辑课程信息</el-button>
          </router-link>
          <router-link :to="'/teach/course/chapter/'+scope.row.id">
            <el-button type="text" size="mini" icon="el-icon-edit">编辑课程大纲</el-button>
          </router-link>
          <el-button type="text" size="mini" icon="el-icon-delete" @click="removeCourseById(scope.row.id)">删除课程
          </el-button>
        </template>
      </el-table-column>
    </el-table>

    <!-- 分页 -->
    <el-pagination
      :current-page="current"
      :page-size="limit"
      :total="total"
      style="padding: 30px 0; text-align: center;"
      layout="total, prev, pager, next, jumper"
      @current-change="getCourseList"
    />

  </div>
</template>

<script>
  import course from "@/api/teach/course";
  import subject from "@/api/teach/subject";
  import teacher from "@/api/teach/teacher";

  export default {
    name: "list",
    data() {
      return {
        searchObj: {
          subjectParentId: '',//一级分类id
          subjectId: '',//二级分类id
          teacherId: '',//讲师id
          title: '',//课程标题
        },//查询表单
        oneSubjectList: [],//一级分类集合
        twoSubjectList: [],//二级分类集合
        teacherList: [],//讲师集合
        listLoading: false,//加载进度
        courseList: [],//数据集合
        current: 1,//当前页
        limit: 5,//每页显示记录数
        total: 0,//总记录数

      }
    },
    created() {
      //初始化课程列表
      this.getCourseList()
      //初始化分类
      this.getSubject()
      //初始化讲师下拉列表
      this.getTeacher()
    },
    methods: {
      //删除课程
      removeCourseById(courseId) {
        //弹框提示
        this.$confirm('此操作将永久删除该课程, 是否继续?', '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).then(() => {//点击确定调用
          course.removeCourse(courseId)
            .then(response => {//删除成功
              this.$message({
                type: 'success',
                message: response.message
              });
              //刷新页面
              this.getCourseList(1)

            })
            .catch(response => {//删除失败
              this.$message({
                type: 'error',
                message: response.message
              })
            })

        }).catch(() => {//点击取消调用
          this.$message({
            type: 'info',
            message: '已取消删除'
          });
        });
      },
      //初始化讲师列表
      getTeacher() {
        teacher.getList()
          .then(response => {
            this.teacherList = response.data.teacherList
          })
      },
      //点击一级分类显示对应二级分类 参数value就是一级分类的id
      subjectLevelOneChanged(value) {
        //遍历一级分类
        for (let i = 0; i < this.oneSubjectList.length; i++) {
          //获取每一个一级分类
          let oneSubject = this.oneSubjectList[i]
          //判断当前点击的一级分类和所有的一级分类id是否相同
          if (oneSubject.id === value) {
            //获取二级分类
            this.twoSubjectList = oneSubject.children
            //清空二级分类id
            this.twoSubjectList.id = ''
          }
        }
      },
      //初始化分类
      getSubject() {
        subject.querySubjectList()
          .then(response => {
            this.oneSubjectList = response.data.subjectVoList
          })
      },
      //获取课程列表集合
      getCourseList(current = 1) {
        this.current = current
        course.pageCourse(this.current, this.limit, this.searchObj)
          .then(response => {
            this.courseList = response.data.pageList
            this.total = response.data.total
          })
      },
      //清空查询表单
      resetData() {
        this.searchObj = {};//清空表单
        this.getCourseList();//查询所有
      }

    }
  }
</script>

<style scoped>
  .myClassList .info {
    width: 450px;
    overflow: hidden;
  }

  .myClassList .info .pic {
    width: 150px;
    height: 90px;
    overflow: hidden;
    float: left;
  }

  .myClassList .info .pic a {
    display: block;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
  }

  .myClassList .info .pic img {
    display: block;
    width: 100%;
  }

  .myClassList td .info .title {
    width: 280px;
    float: right;
    height: 90px;
  }

  .myClassList td .info .title a {
    display: block;
    height: 48px;
    line-height: 24px;
    overflow: hidden;
    color: #00baf2;
    margin-bottom: 12px;
  }

  .myClassList td .info .title p {
    line-height: 20px;
    margin-top: 5px;
    color: #818181;
  }
</style>
